baikuza wrote:Varanus komodoensis do not have any poison. it just make infection by the bacteria or other microorganism in the mouth.

Actually that's been proven incorrect. Dr. Bryan Fry, an Australian toxicologist published a study last year documenting the presense of venom glands in Varanids and other rather surprising genera. The nasty bite of a komodo dragon was venom all along. Everyone 'knew' that monitors didn't have venom and therefore it had to be something else, so they thought it was bacteria.

There are only two lizards considered venomous, the Beaded Lizard (Heloderma horridurn), and the Gila monster (Heloderma suspectum). Although not strictly venomous, the bite of a Komodo Dragon is not just dangerous for the physical damage the Komodo is capable of causing, it is also heavily dosed with dangerous bacteria.

Within the Komodo's saliva reside more than fifty strains of bacteria, some seven of which are highly septic and four of which have no known specific antidote. Addressed early, attacks on humans have not proven fatal when treated with broad based and powerful antibiotics. However for animals in the wild, the bite usually proves fatal as a result of infection, even if the wound itself is insufficient.

Despite the toxicity of a Komodo Dragon's bite, Komodo Dragons bitten by their own species seem unaffected by the bacteria. As a result, the Komodo makes an interesting study in terms of both the toxicity of its saliva and the impregnable nature of its immune system. Some of the zoological studies of the Komodo Dragon are focussed on this particular aspect of the Komodo Dragons make-up

Skeletor Rinpoche wrote:I would have to say the most venomous animal is the box jellyfish or the new species that has just been documented, which is only the size of a human thumbnail

The original question is a hard one to answer, defining the difference between poisonous venomous and toxic.

To define the meaning between the two words snakes technically are not “poisonous” as a poison must be ingested orally, venom being introduced directly into the bloodstream or underlying tissue via the reptiles fangs.

Then there is "danger scores" to take into consideration also as in ....
Danger scores are used by rating five aspects of snake bite they are as follows.
1) Venom toxicity
2) Venom yield
3) Fang length
4) Temperament
5) Frequency of bite

Then you have LD50, LD50 is a measurement used in Laboratories meaning –lethal dose as in the dose of venom that will result in the deaths of 50% of the test subjects.

LD50 is expressed in Mg/ Kg per body weight the lower the toxicity number the more venomous the organism.

So, taking all the above into consideration the question can have many answers.

The most venomous animal is an insect found only in the Sinai Desert called the " Afrur " which is hebrew for dirt. This insect is related to the bedbug and was discovered in 1967 after Isreal foung numerous soldiers dead on bivouac with an unknown toxin found in their blood. This insect is so venomous that it is considered 100 times more toxic than the saw-scaled viper or scorpions in the region. It is so unknown that it is extemely difficult to find any info on the web, unless you can research it through Jerusalem University. A mouse injected with cobra venom will live for about a minute to a minute and a half, the Afrur will kill it in 3 seconds! The insect injects the venom through a probosis and its venom gland is 1/3 of its body. What the hell does it eat? Why so venomous?

I've often wondered about this too. Unfortunately (or fortunately!) I don't think there's any definitive answer is there? I'm sure we can tell what's most dangerous to a mouse, etc, but not us. It would pretty unethical to poison people & see what happens!

Honestly though, if it kills you, it doesn't matter how poisonous it was - it did it's job.

There is a fish on Adriatic sea and if you step on it you will get a terrible painful feeling, after 10 minutes your leg will be swalled. It is no more than 3-5 cm long and it has a kind of sting on his spinal corde.
I will look forward to find the name.